Loose leaf binder



2 Sheets-Sheet 1 INI/ENTOR. PAUL O. UNGEQ ATTORNEY.

P. O. UNGER LOOSE LEAF BINDER Filed Sept. ll, 1953 June 3o, 1936.

Jim@ 3057 E936. P. o. UNGER LoosE LEAF BINDER Filed Sept. l1, 1953 2Sheets-Sheet 2 llllllllll/llllllllzflllllll/lllzh Patented June 30, 1936UNTED STATES PATENT GFFICE LOOSE LEAF BINDER Application September 11,1933, Serial No. 688,890

8 Claims.

This invention relates to loose leaf binders, and particularly to a newand improved locking mechanism for the same. In certain types of looseleaf binders, the sides of the binder may be expanded or contractedthrough the use of telescopic posts. Springs are usually conned incertain posts and are designed for expanding or separating the twobinder heads. Locking mechanism is usually provided in other posts forresisting the tendency of the springs to expand the binder. Thisinvention is particularly concerned with the locking means in certain ofthe telescopic posts for locking the binder heads in their adjustedposition. l

It is an object of this invention to provide a locking post that is easyto assemble, and is efficient and durable in operation. It is a furtherobject of this invention to provide a locking post in which the actionof the locking mechanism is controlled by gravity. It is a furtherobject of this invention to provide a locking post with simple andeiiicient means to prevent failure of the locking elements tofunctionrproperly under any conditions. Other objects of this inventionwill become apparent upon reading thefollowing description taken inconjunction with the accompanying drawings in which: n

Figure 1 is a top plan view of the binder back broken away in parts tofacilitate illustration;

Figure 2 is a cross sectional View taken upon the line I-II of Figure 1looking in the direction of the arrows; l

Figure 3 is an enlarged sectional view' through one of the locking postsillustrated in Figure 1;

vFigure 4 is a view similar to Figure 3 showing the locking post in openposition;

Figure 5 is an enlarged sectional view through a modified form oflocking post showing the post in locked position; p p

.Figure 6 illustrates the locking post of Figure 5 in open position;

Figure 7 is an enlarged sectional view through another modied form oflocking post showing the locking post in locked position; and

Figure 8 illustrates the locking post of Figure 7 in open position.

The loose leaf binder to which this invention is applied consists of apair of clamping or back members 2 and 3 which are movable transverselyrelative to each other. Cover members 4 are hinged to the back members,asl indicated at 5. The ends of the back member 2.are`bent over, asindicated at 5, to form guide l'channels in which the ends of the backmember 3 are moved. Interengaging tongues 'I and 8 on the bent overportion E and the back member 3, respectively, prevent separation of theback members.

A pair of metal plates 9 and II) is rigidly secured to the back members2 and 3 so as to form a tubular compartment II adjacent the outer edgesof the back members 2 and 3. The compartments II extend the length ofthe binder back and are closed at the ends by end caps I2 of felt orsuitable material to prevent the binder from marring any finishedsurface on which it may be handled. The back members 2 and 3 areconnected by a pair of posts I3 each of which consists of a tubularsection I 4 rigidly secured to the plate 9, as shown at I5, and a secondtubular section IB secured to the plate I0, as shown at I'l, and adaptedto telescope into the section I4. A coiled spring I8 is contained withinthe telescopic post I3 and normally tends to expand to separate the backmembers 2 and 3. The back members 2 and 3 are also connected by a pairof telescopic locking posts I9.

Each locking post I9 consists of a tubular section 2U Vrigidly securedto the plate I9, as shown at 2 I, and a solid section 22, rigidlysecured to the plate 9, as shown at 23, and adapted to telescope intothe tubular section 20. The solid section 22 is provided with aplurality of notches 24 adjacent its inner end. Each notch has onehorizontal wall 25 and an inclined wall 26. In my preferred embodiment Ihave shown four notches arranged in diametrically opposite pairs withone pair at a different level from the other and at right anglesthereto. However, it is obvious that the number and arrangement of thenotches may be varied at will.

Each notch is provided with a gravity operated locking plate 2l. Theselocking plates are thin metallic wafers having a shape approximatelythat of a semi-circle. The width of the locking plate measuredoutwardly, that is the distance from the center of the chordconstituting the straight side of the plate to the center of the arcconstituting the curved side of the plate, is greater than the radialcorresponding width of the horizontal surface 25 of the notch 24, butless than the corresponding width of the inclined surface 26 of thenotch. This causes the locking plates 2l to lie adjacent the inclinedsurface 28 out of holding contact with the tubular section 20 to permitr expansion of the binder when the locking post I9 is in the openposition illustrated in Figure 4. It will be understood that theexpansive force of the coiled springs I8 will continue to hold thelocking parts in engagement even when the binder is reversed from theposition shown in Figure 3 to Y that shown in Figure 4. A slightpressure applied gravity causes the plates 21 to move toward the'horizontal surface' into holding contact with the tubular section 2@ toprevent expansion of the binder. Although the inclined surface 26 of thenotch 24 might be left smooth, I prefer to pro- Vvide a projection 28 toeliminate any possibility of adhesion of the locking plate 2l to theinclined Ysurface 26 when the `locking post occupies the position ofFigure 3. Y Y

` The interior surface of the tubular section 20 of the locking post isroughened to provide a suitable holding surface for the lockingV plates21. As

' shown in Figures Sand 4,'the preferred form of roughenedsurfaceconsists ofthe provision of a double thread 29 which extends oversubstantially the entire interior surface of the tubular section.

f The double thread is preferred because it allows the Vlocking platesin diametrically opposite notches at the same level to engage the troughof the thread at the Vsarne time. The second pair of notches are spacedat right angles to the `rst pair and are spaced vertically therefrom adistance equal to a multiple of one half the pitch of the thread plusone fourth of the -pitch so that the locking plates positioned thereinwill engage the trough of the thread at the same time as the rst pair.This arrangement of parts insures engagement of all four locking plateslwith the trough of the thread at the same time so that the full benefitof' the multiplicity of locking plates is realized.

While in the` preferred embodiment of my invention, illustrated inFigures yl to 4 inclusive, the interiorV surface of the tubular section20 of the Vlocking postV i9 is roughened, this feature is not essentialto the invention as the interior surface may be substantially smooth. Inthis event'the frictional contactV of the locking plate 2l will serve tohold the sections of the locking post against expansion.

The modied embodiment of my invention illustrated-in Figures 5 and 6differs from the preferred embodiment only in that the solid section 3l!of the locking post is provided with a longitudinal recess 3! in which agravity operated rod 32 is positioned. When the locking post is in theopen position illustrated in Figure 6, the rod 32 lies below theinclined surface 33 of the notch 34 and does not interfere with theexpansion of the post. When the binder is inverted so that the lookingpost occupies the position illustrated in Figure 5, the gravity rods 32fall against the locking plates 21 to force them into holding contactwith the trough of the thread 29. Y Y

The modiiication illustrated in Figures 7 and 3 includes a fixed pin 35bridging the notch 36.

The locking plates 3l are provided with a recess scope of myV invention.

claims, Y Y

I claim: l 1. A locking post including a pair of telescopic sections,the inner section being provided with a notch having a substantiallyhorizontal wall andv a second wall extending at an acute angle to saidrst mentioned wall, and a flat locking element positioned with an edgein'said notch, the width of said locking element measured outwardlybeing greater than the corresponding width of said first I mentionedWall and less than the corresponding width of said second mentionedwall. f

2. In a loose leaf binder, a locking post comprising a pair oftelescopic sections, one of said Ysections being provided with a-notchhaving a substantially horizontal wall and anV inclined wall, Y

a locking element positioned in said notch, and a projection on saidinclined wall to preventadhesion of'V said locking element to saidVinclined wall.

3. In a loose leaf binder, a locking post comprising aV pair-oftelescopic sections, one of said sections having a notch, a lockingelement in said notch, a recess in said locking element, and a pinbridging saidj notch vertically and engaging' said recess to guide saidlocking element.

4. In a lockingpost for loose leaf binders, an inner section providedwith an inclined V-shaped notch, a tubular outer section telescopingover said inner section, and a locking plate positioned in said notchwith one edge adjacent the apex of said V-shapedV notch, said lockingplate being actuatable by gravity to pivot on its inner edge from openrto locking position.

5. In a locking post for loose leaf binders, aV

' ment with the outer section.

6. A locking post comprising a pair of telescoping sections, one of saidsectionsbeing provided with a notch having an inclined Wall, and alocking platein said notch, said locking plate lying against saidinclined wall out of locking engagement when said post is in onevertical position and pivoting in the angle of the notch into lockingengagement rwhen said post is inverted.

'7. A locking post comprising a pair of telescopic sections, one of`said Ysections having a notch, and a locking plate disposed in saidnotch crosswise of said section and bearing against the other sectionYfor locking said sections together, Vsaid locking plate beingnormallyinclined with respect to the post and actuatable by gravity when saidpost is in a vertical position;

8. A locking post comprising a pair of telescopic sectionsfthe innersection having a notch with one wall inclined with respect Vto saidsection and another wall at right angles thereto, and a locking elementpositioned in said notch, said locking element being approximately theshape of a segment of a circle, the maximum dimension across saidlocking element perpendicular to the iiat edge being less thanthecorresponding dimension Vacross the inclined wall of said notch andgreater than the corresponding dimension across said second mentionedwall.

PAUL O.UNGEEL

